Valves may be utilized to selectively open and close a fluid passage through a valve housing to selectively allow or prevent flow through the passage. Specifically, the valve body may be actuated into a position in which it engages a valve seat to seal the passage such that a fluid may not traverse the passage (or at least flow is restricted relative to a valve open position). The valve can further be actuated to a position in which it is not fully seated against the valve seat to allow a flow of fluid through the passage.
Referring to FIG. 1, valve 20 includes housing 22 defining inlet 24 and outlet 26 which are fluidly connected by a passage defined within housing 22 and extending between inlet 24 and outlet 26. Inlet 24 and outlet 26 are fluidly connected so that flow F can enter housing 22 at inlet 24, traverse the passage and exit housing 22 at outlet 26. Valve 20 is a bi-directional valve, which means that inlet 24 and outlet 26 may be functionally switched such that fluid can flow in a direction opposite to the direction of flow F illustrated in FIG. 1 so that flow through valve 20 enters through “outlet” 26, traverses the passage defined within housing 22 and exits housing 22 at “inlet” 24.
Valve body 28 is rotatably supported on trunnion 31 relative to housing 22. Actuation of trunnion 31 actuates valve body 28 between the open position illustrated in FIG. 1 in which valve body 28, which is a butterfly valve, is aligned with the direction of flow F to allow flow F to enter housing 22 at inlet 24, traverse the passage through housing 22 and exit housing 22 at outlet 26, to a closed position in which valve body 28 is transverse to the passage through housing 22 such that valve body 28 blocks the passage through housing 22 to restrict flow F through the passage.
In the closed position, valve body 28 sealingly engages valve seat 30 about perimeter 32 of valve body 28 to block the flow of fluid through valve 20. In the open configuration illustrated in FIG. 1, valve body 28 presses against valve seat 30 in a non-uniform manner, i.e., valve body 28 presses against valve seat 30 at only two discrete areas of contact, one of which is illustrated in FIG. 2. Contrary to this concentration of force at only two areas on valve seat 30 in the open position, valve body 28 provides a substantially uniform force about perimeter 32 in the closed position because perimeter 32 sealingly engages (i.e., frictionally engages) valve seat 30 uniformly about the annular valve seat.
As illustrated in FIG. 2, in the open configuration valve body 28 impinges on valve seat 30 and forms depression 34, as illustrated in FIG. 3. If valve body 28 maintains the open position for an extended period of time, valve seat 30, which may be formed of a thermoplastic elastomer, may plastically deform at depression 34. Even if valve seat 30 is not plastically deformed to define depression 34, valve seat 30 may not have sufficient elastic properties to fully return to the shape it held prior to the formation of depression 34. In either event, if valve body 28 is closed after depressions 34 are formed (one each, located 180 degrees apart about the inner circumference of valve seat 30, if the valve is left in the fully open position), then depressions 34 will cause leak points in the valve because valve body 28 will not be able to fully seal around its entire perimeter 32, because depressions 34 will be spaced from perimeter 32 of valve body 28. Depressions 34 can also be formed at positions spaced less than 180 degrees if the valve is left in an open position that does not correspond to its fully opened position.
To obviate the formation of depressions 34, a valve in accordance with the present disclosure mechanically links the valve body to the valve seat such that the valve seat automatically moves to a position spaced from the valve body as the valve body is moved from a closed position to an open position. The resulting spaced-apart configuration of the valve body and valve seat in the open position eliminates impingement and the resulting depressions 34.
In an exemplification thereof, the present disclosure provides a valve including a housing having an inlet and an outlet fluidly connected by a passage, so that a flow of fluid can enter the housing at the inlet, traverse the passage, and exit the housing at the outlet. The valve of this exemplification of the present disclosure further includes a valve body movable between a valve body closed position and a valve body open position, the valve body blocking the passage when the valve body maintains the valve body closed position such that the valve body is operable to restrict the flow of fluid through the passage when the valve body maintains the valve body closed position, the valve body opening the passage when the valve body maintains the valve body open position such that the valve body is operable to allow the flow through the passage when the valve body maintains the valve body open position. The valve of this exemplification of the present disclosure further includes a valve seat positioned within the housing and movable relative to both the housing and the valve body between a seating position and a valve seat open position, the valve body seating with the valve seat to enable restriction of the flow of fluid through the passage when the valve body maintains the valve body closed position and the valve seat maintains the seating the position, the valve seat spaced from the valve body when the valve seat maintains the valve seat open position such that the valve body cannot contact the valve seat when the valve seat maintains the valve seat open position, whereby the valve body does not impinge on the valve seat when the valve seat maintains the valve seat open position and the valve body maintains the valve body open position, the valve seat mechanically link to the valve body such that the valve seat automatically moves from the seating position to the valve seat open position as the valve body is moved from the valve body closed position to the valve body open position. In a variation of this exemplification of the present disclosure, an actuator is interposed between the valve body and the valve seat and is operable to move the valve seat from the seating position to the valve seat open position in response to the valve body moving from the valve body closed position to the valve body open position. The actuator may comprise a cam secured relative to the valve body such that the cam actuates the valve seat from the seating position to the valve seat open position as the valve body is moved from the valve body closed position to the valve body open position.
In another exemplification thereof, the present disclosure provides a valve including a housing having an inlet and an outlet fluidly connected by a passage, whereby a flow of fluid can enter the housing at the inlet, traverse the passage, and exit the housing at the outlet. This exemplification of the present disclosure further includes a valve body movable between a valve body closed position and a valve body open position, the valve body blocking the passage when the valve body maintains the valve body closed position such that the valve body is operable to restrict the flow of fluid through the passage when the valve body maintains the valve body closed position, the valve body opening the passage when the valve body maintains the valve body open position such that the valve body is operable to allow the flow through the passage when the valve body maintains the valve body open position. This exemplification of the present disclosure further includes a valve seat positioned within the housing, the valve seat movable relative to both the housing and the valve body between a seating position and a valve seat open position, the valve body seating with the valve seat to enable restriction of the flow of fluid through the passage when the valve body maintains the valve body closed position and the valve seat maintains the seating position, the valve seat spaced from the valve body when the valve seat maintains the valve seat open position such that the valve body cannot contact the valve seat when the valve seat maintains the valve seat open position, whereby the valve body does not impinge on the valve seat when the valve seat maintains the valve seat open position and the valve body maintains the valve body open position. This exemplification of the present disclosure further includes means for mechanically linking the valve body to the valve seat and for automatically moving the valve seat from the seating position to the valve seat open position as the valve body is moved from the valve body closed position to the valve body open position. In a variation of this exemplification of the present disclosure, the means for mechanically linking the valve body to the valve seat may comprise a cam secured relative to the valve body such that the cam actuates the valve seat from the seating position to the valve seat open position as the valve body is moved from the valve body closed position to the valve body open position.
In a further exemplification thereof, the present disclosure provides a method of preventing deformation of a valve seat of a valve when a valve body of the valve maintains an open position, the valve including: a housing having an inlet and an outlet fluidly connected by a passage, whereby a flow of fluid can enter the housing at the inlet, traverse the passage, and exit the housing at the outlet; the valve seat and the valve body positioned in the housing; the valve body movable between a valve body closed position and a valve body open position, the valve body blocking the passage when the valve body maintains the valve body closed position to enable restriction of the flow of fluid through the passage when the valve body maintains the valve body closed position, the valve body opening the passage when the valve body maintains the valve body open position to enable allowance of the flow through the passage when the valve body maintains the valve body open position. In this exemplification of the present disclosure, the method comprises the steps of: automatically moving the valve seat relative to both the housing and the valve body from a seating position in which the valve body seats with the valve seat such that the valve body is operable to restrict the flow of fluid through the passage when the valve body maintains the valve body closed position and the valve seat maintains the seating position to a valve seat open position in which the valve seat is spaced from the valve body such that the valve body cannot contact the valve seat when the valve seat maintains the valve seat open position when the valve body is moved from the valve body closed position to the valve body open position, whereby the valve body does not impinge on the valve seat when the valve seat maintains the valve seat open position and the valve body maintains the valve body open position.
The above-mentioned and other features of the invention and the manner of obtaining them will become more apparent and the invention itself will be better understood by reference to the following description of exemplary embodiments of the invention taken in conjunction with the accompanying drawings. These above-mentioned and other features of the invention may be used in any combination or permutation.
Corresponding reference characters indicate corresponding parts throughout the several views. Although the drawings represent embodiments of the present invention, the drawings are not necessarily to scale and certain features may be exaggerated in order to better illustrate and explain the present invention. The exemplifications set out herein illustrate embodiments of the invention, and such exemplifications are not to be construed as limiting the scope of the invention in any manner.